Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0026838 (spasticity)
 6,471 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Lesch-Nyhan syndrome is associated with complete deficiency of hypoxanthine-guanine phosphoribosyltransferase (HPRT), characterized by hyperuricemia and severe neurological signs. The HPRT gene has been mapped to the q26 region on the long arm of the X-chromosome. We are taking care of a family of Lesch-Nyhan syndrome. A 14-year-old male was noted the growth disturbance at the age of 7 months and self-mutilation behavior characterized by compulsive biting of his lip and fingers at the age of 18 months. In 1987, at the age of 4, he was diagnosed as Lesch-Nyhan syndrome from neurologic signs and hyperuricemia (9.8 mg/dl). Neurological examination revealed mild mental and growth retardation, spasticity and hyperreflexia of lower extremities, choreoathetoid movements of extremities, and compulsive self-mutilation. The HPRT activity in erythrocytes of this patient was 0.02 nmol/min/mg hemoglobin (control value 1.76 +/- 0.06), and adenine phosphoribosyltransferase (APRT) activity was 1.08 nmol/min/mg hemoglobin (control value 0.43 +/- 0.06). Using polymerase chain reaction (PCR) method coupled with direct sequencing, we analyzed the nucleotide sequences of each exon from the genomic DNA as well as the entire HPRT coding region of the cDNA by RT-PCR method. In the HPRT gene from the patient, a guanine to adenine substitution at base position 209 in exon 3 was identified, which resulted in a single amino acid substitution of glycine with glutamic acid at codon 70. The family studies indicated that his mother, sister and grandmother were heterozygotes. PCR-restriction fragment length polymorphism (RFLP) utilizing Mnl I site which created by the mutation, was useful for detection of the mutant gene. We have identified a new missense mutation of the HPRT gene in a Japanese patient. This mutation was reported at the same codon as foreign mutants and mighty be indicative of a location of mutation activity in the HPRT gene.
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PMID:[A Japanese family with Lesch-Nyhan syndrome resulting from a new point mutation in hypoxanthine-guanine phosphoribosyltransferase gene]. 939 32

Deficiency of liver arginase (AI) causes hyperargininemia (OMIM 207800), a disorder characterized by progressive mental impairment, growth retardation, and spasticity and punctuated by sometimes fatal episodes of hyperammonemia. We constructed a knockout mouse strain carrying a nonfunctional AI gene by homologous recombination. Arginase AI knockout mice completely lacked liver arginase (AI) activity, exhibited severe symptoms of hyperammonemia, and died between postnatal days 10 and 14. During hyperammonemic crisis, plasma ammonia levels of these mice increased >10-fold compared to those for normal animals. Livers of AI-deficient animals showed hepatocyte abnormalities, including cell swelling and inclusions. Plasma amino acid analysis showed the mean arginine level in knockouts to be approximately fourfold greater than that for the wild type and threefold greater than that for heterozygotes; the mean proline level was approximately one-third and the ornithine level was one-half of the proline and ornithine levels, respectively, for wild-type or heterozygote mice--understandable biochemical consequences of arginase deficiency. Glutamic acid, citrulline, and histidine levels were about 1.5-fold higher than those seen in the phenotypically normal animals. Concentrations of the branched-chain amino acids valine, isoleucine, and leucine were 0.4 to 0.5 times the concentrations seen in phenotypically normal animals. In summary, the AI-deficient mouse duplicates several pathobiological aspects of the human condition and should prove to be a useful model for further study of the disease mechanism(s) and to explore treatment options, such as pharmaceutical administration of sodium phenylbutyrate and/or ornithine and development of gene therapy protocols.
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PMID:Mouse model for human arginase deficiency. 1205 59

gamma-Aminobutyric acid (GABA) is the primary inhibitory neurotransmitter in the central nervous system. GABA is converted from glutamic acid by the action of glutamic acid decarboxylase (GAD) of which two isoforms exist GAD65 and GAD67. GABA then is broken down, both within the cell and in the synaptic cleft by GABA transaminase to form succinic semialdehyde. In turn, succinic semialdehyde is converted either to succinic acid by succinic semialdehyde dehydrogenase or into gamma-hydroxybutyric acid (GHB) by succinic semialdehyde reductase. Because GABA modulates the majority of inhibition that is ongoing in the brain, perturbations in GABAergic inhibition have the potential to result in seizures. Therefore, the most common disorder in which GABA is targeted as a treatment is epilepsy. However, other disorders such as psychiatric disease, spasticity, and stiff-person syndrome all have been related to disorders of GABAergic function in the brain. This review covers the roles of GABAergic neurotransmission in epilepsy, anxiety disorders, schizophrenia, stiff-person syndrome, and premenstrual dysphoric disorder. In the final section of this review, the GABA metabolite GHB is discussed in terms of its physiological significance and its role in epilepsy, sleep disorders, drug and alcohol addiction, and an inborn error of GABA metabolism, succinic semialdehyde dehydrogenase deficiency.
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PMID:GABA, gamma-hydroxybutyric acid, and neurological disease. 1289 48

Bosch-Boonstra-Schaaf optic atrophy syndrome (BBSOAS) is a recently described autosomal dominant disorder caused by mutations in the nuclear receptor subfamily 2 group F member 1 (NR2F1) gene. Its common features include optic atrophy and/or hypoplasia, developmental delay, intellectual disability, attention deficit disorder, autism spectrum disorder, seizures, hearing defects, spasticity, hypotonia, and thinning of the corpus callosum. Mitochondrial involvement has also been described with BBSOAS. Currently, 31 cases of BBSOAS have been described in the literature. Here we report a case of undiagnosed BBSOAS presenting as psychosis in a 32-year-old man with a history of bilateral optic nerve atrophy, intellectual disability, epilepsy, and mitochondrial complex I abnormality on muscle biopsy. Whole-genome sequencing identified a heterozygous de novo nonsense mutation in the NR2F1 gene [c.253 G>T (guanine to thymine mutation in coding position 253) in exon 1, p.E85X variant (GAG>TAG) (glutamic acid to stop codon mutation; protein truncated to 85 amino acids)]. A pathogenic nonsense mutation has not previously been reported in the literature in association with BBSOAS and represents an expansion of clinically relevant variants. Psychosis has also not been previously reported in this syndrome and may represent a phenotypic expansion of BBSOAS, a manifestation of prolonged disease, or a result of disease management.
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PMID:Bosch-Boonstra-Schaaf Optic Atrophy Syndrome Presenting as New-Onset Psychosis in a 32-Year-Old Man: A Case Report and Literature Review. 3191 71

Bosch-Boonstra-Schaaf optic atrophy syndrome (BBSOAS) is a recently described autosomal dominant disorder caused by mutations in the nuclear receptor subfamily 2 group F member 1 (NR2F1) gene. Its common features include optic atrophy and/or hypoplasia, developmental delay, intellectual disability, attention deficit disorder, autism spectrum disorder, seizures, hearing defects, spasticity, hypotonia, and thinning of the corpus callosum. Mitochondrial involvement has also been described with BBSOAS. Currently, 31 cases of BBSOAS have been described in the literature. Here we report a case of undiagnosed BBSOAS presenting as psychosis in a 32-year-old man with a history of bilateral optic nerve atrophy, intellectual disability, epilepsy, and mitochondrial complex I abnormality on muscle biopsy. Whole-genome sequencing identified a heterozygous de novo nonsense mutation in the NR2F1 gene [c.253 G>T (guanine to thymine mutation in coding position 253) in exon 1, p.E85X variant (GAG>TAG) (glutamic acid to stop codon mutation; protein truncated to 85 amino acids)]. A pathogenic nonsense mutation has not previously been reported in the literature in association with BBSOAS and represents an expansion of clinically relevant variants. Psychosis has also not been previously reported in this syndrome and may represent a phenotypic expansion of BBSOAS, a manifestation of prolonged disease, or a result of disease management.
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PMID:Commentary on "Bosch-Boonstra-Schaaf Optic Atrophy Syndrome Presenting as New-Onset Psychosis in a 32-Year-Old Man: A Case Report and Literature Review". 3191 72